Cracked Players Blocked at Handshake (Invalid Session) | Velocity + Minekube Gate | Zero Logs on Proxy

[KikoStudios]

Description: I am running a Minecraft 1.21.1 Fabric server behind a Velocity proxy using Minekube (Gate). My goal is to allow both Premium and Offline-mode (Cracked) players to connect. However, I am hitting a silent block where cracked players are prevented from joining while Premium players work fine.

The Problem: When an offline-mode (cracked) player tries to connect, they receive the error: Failed to login: Invalid session (Try restarting your game).

The Silent Bug:

Zero Console Output: There is absolutely no log in the Velocity console or the Fabric server console when this happens. The proxy does not show any connection attempt, meaning the packet is dropped or rejected before Velocity can even process the player.

Computer Difference: The exact same files and configurations work perfectly on my Windows 11 notebook (both premium and cracked can join). The issue only happens when running the setup on my Windows 10 machine.

Troubleshooting Already Attempted:

Firewall and Control Panel: I have gone into the Windows Control Panel and ensured all Java (TM) Platform SE Binary entries are allowed through the Firewall for both Private and Public networks.

Loopback Exemptions: I have tried enabling loopback exemptions for the network stack to ensure local processes can communicate.

Config Verification: Verified online-mode = false in velocity.toml and the backend server.properties.

Forwarding: player-info-forwarding-mode is set to modern with matching secrets.

Why this is frustrating: Because there are no logs on the proxy side or the server side, I cannot debug where the rejection is happening. It seems like the handshake is being intercepted or blocked at the OS or Minekube Gate layer specifically for unauthenticated sessions.